Intra-strain Elicitation and Suppression of Plant Immunity by Ralstonia solanacearum Type-III Effectors in Nicotiana benthamiana  

作　　者：Yuying Sang Wenjia Yu Haiyan Zhuang Yali Wei Lida Derevnina Gang Yu Jiamin Luo Alberto P.Macho 

机构地区：[1]Shanghai Center for Plant Stress Biology,CAS Center for Excellence in Molecular Plant Sciences,Shanghai Institutes of Biological Sciences,Chinese Academy of Sciences,Shanghai 201602,China [2]University of Chinese Academy of Sciences,Beijing,China [3]The Sainsbury Laboratory,University of East Anglia,Norwich Research Park,Norwich NR47UH,UK

出　　处：《Plant Communications》2020年第4期87-100,共14页植物通讯（英文）

基　　金：supported by the Strategic Priority Research Program of the Chinese Academy of Sciences(grant XDB27040204);the National Natural Science Foundation of China(grant 31571973);the Chinese 1000 Talents Program,and the Shanghai Center for Plant Stress Biology(Chinese Academy of Sciences).

摘　　要：Effector proteins delivered inside plant cells are powerful weapons for bacterial pathogens,but this exposes the pathogen to potential recognition by the plant immune system.Therefore,the effector repertoire of a given pathogen must be balanced for a successful infection.Ralstonia solanacearum is an aggressive pathogen with a large repertoire of secreted effectors.One of these effectors,RipE1,is conserved in most R.solanacearum strains sequenced to date.In this work,we found that RipE1 triggers immunity in N.benthamiana,which requires the immune regulator SGT1,but not EDS1 or NRCs.Interestingly,RipE1-triggered immunity induces the accumulation of salicylic acid(SA)and the overexpression of several genes encoding phenylalanine-ammonia lyases(PALs),suggesting that the unconventional PALmediated pathway is responsible for the observed SA biosynthesis.Surprisingly,RipE1 recognition also induces the expression of jasmonic acid(JA)-responsive genes and JA biosynthesis,suggesting that both SA and JA may act cooperatively in response to RipE1.We further found that RipE1 expression leads to the accumulation of glutathione in plant cells,which precedes the activation of immune responses.R.solanacearum secretes another effector,RipAY,which is known to inhibit immune responses by degrading cellular glutathione.Accordingly,RipAY inhibits RipE1-triggered immune responses.This work shows a strategy employed by R.solanacearum to counteract the perception of its effector proteins by plant immune system.

关 键 词：ETI SGT1 EFFECTOR immunity Ralstonia PAL 

分 类 号：S43[农业科学—农业昆虫与害虫防治]